How do you desensitize a horse to tarps, tarps in trees, and tarps blowing in wind?

A stationary tarp on the ground and a tarp blowing in a tree are effectively two different stimuli for a horse, and desensitizing to one does not automatically transfer to the other. Clinton Anderson addresses the progression from static to dynamic tarp exposure as a systematic sequence that builds the horse's confidence with tarps in all the forms they are likely to appear. The ground tarp sequence — described in the companion entry on tarp desensitization — produces a horse comfortable with a tarp underfoot and draped on its body. Anderson then progresses to tarps in motion: holding one end of a tarp while an assistant holds the other, creating a sail-like surface that moves in the wind and makes unpredictable snapping sounds. The horse is worked near this moving tarp using approach and retreat until it can stand next to it and eventually walk through it without concern. Tarps in trees — a common obstacle on competitive trail courses — add the overhead element that horses find most alarming because things appearing above them trigger the most primal predator response. Anderson introduces overhead tarp exposure by first working a horse under stationary tarps hung high enough not to touch the horse, then progressively lowering and animating them. The horse learns that tarps touching and moving over its back are safe through the same progressive sequence used for ground tarps. The wind element requires specific attention because wind makes the tarp unpredictable — it can suddenly snap loudly or billow toward the horse without the handler controlling it. Anderson uses windy days specifically for tarp work in advanced stages of desensitization, because the unpredictability of wind-driven movement is exactly what the horse will encounter in real situations on the trail or at a show. A horse that can handle a wind-driven tarp has a high tolerance for unpredictable movement in general.